Ferguson also wrote the second part of "No Protestant Plot," another very violent pamphlet, and several treatises on the same subject. Meanwhile, other means were prepared to effect the desired change of government. It is not necessary to enter particularly into the well-known history of the Rye-house plot. Every body knows, that, while Russel, Sidney, Monmouth, and others, undertook to raise an insurrection in the country, Shaftesbury promised to head ten thousand brisk boys in the city of London. Among these brisk boys were a fanatic party, who agitated projects of assassinating the King and the Duke of York, unknown to the more generous nobles, who proposed only to secure the king's person. In all and each of these cabals, Ferguson acted a distinguished part. When Shaftesbury fled from his house into lurking places about Wapping, he trusted Ferguson with the secret of his residence, although concealed from the noble-minded Russel, and the generous Monmouth. By his intervention, he heartened and encouraged the associates to break forth into open insurrection. With the inferior conspirators, Ferguson was yet more intimate, and seems, in fact, to have given life to the vague and desperate plans of _lopping_, as they called the assassination of the royal brothers, by the countenance which he pretended to procure the conspirators from those of superior rank. He told West, he would procure the Duke of Monmouth's written consent to his father's murder; although he afterwards allowed, he durst not even mention such a plan to him. At length, when Shaftesbury, weary of the delays of the other conspirators, left England for ever, Ferguson and Walcot were the companions of his flight. By this the plan of insurrection was for a time confounded, for the higher order of the malcontents were ignorant of the lines of communication by which the city cabal was conducted. Ferguson was therefore recalled, and in an evil hour returned from Holland. His arrival gave new life both to the upper and inferior conspiracy: in the former, six of the leaders formed themselves into a regular committee, to extend their influence and correspondence through the kingdom, and unite measures with the disaffected in Scotland. The lower band of assassins matured and prepared their plan for assassinating the king and duke as they returned from Newmarket. Ferguson, who still acted in the capacity of treasurer, which Dryden has assigned him, paid for the arms provided for the enterprize; and, by his daring language, encouraged them to proceed. He offered, in mockery, to consecrate the blunderbuss with which Rumbold was to fire into the carriage; and when Sunday was fixed for the day of action, he quoted the old Scottish proverb, "the better day, the better deed." Even when, by the treachery of Keeling, the plot was finally discovered, and the conspirators were dispersing in dismay and terror, Ferguson took his leave of them with great gaiety,